In recent years, with the rapid development of various applications such as information technology, wireless mobile communications, and information appliances, to achieve the objects of greater convenience, lighter weight, and better usability, the input device of many information products has been converted from a traditional keyboard or mouse, etc. to a touch display panel. Touch input techniques include, for instance, a capacitive touch technique, a resistive touch technique, and an optical touch technique. In the case of the capacitive touch technique, in general, electrodes providing driving voltage and electrodes sensing electrical properties are disposed in a dispersed manner. By sensing the capacitance change between the electrodes providing driving voltage and the electrodes sensing electrical properties, touch input techniques can be achieved.
In general, to achieve both display function and touch function, the electrodes providing driving voltage and the electrodes sensing electrical properties can be formed by a conductive film having light-transmittance properties, such as an indium-tin-oxide (ITO) conductive film, or be formed via a trace method by using a metal wire. However, the costs of a conductive film with light-transmittance properties are very high. Moreover, the desired electrodes are formed by winding metal wires via a specific trace method, and although tough sensing can be achieved, the metal wire is exposed on the display panel, thus affecting light uniformity and panel visibility of the display panel.